Mitt Romney had the political stage to himself Thursday night. And the Republican presidential nominee used the spotlight to his advantage.

The former Massachusetts governor had not been the first choice of many at the GOP convention. But delegates in Tampa cheered when he made it clear that a Romney administration would create jobs and control the debt. The roar let the White House know that the game is on.

Naturally, Romney spoke about issues besides the economy. He needed to define himself as a more likable figure, and he did just that — particularly in the introductory film about his life before politics and with anecdotes about family, such as his parents worrying more about what kind of person he would become than what he would do for a living.

But, like Paul Ryan and Chris Christie before him, Romney scored best when focusing on economic growth and the $16 trillion debt.

He rightly explained how the economy had not rejuvenated under President Barack Obama and that the debt had ramped up under him. “This is when our nation was supposed to start paying down the national debt and rolling back those massive deficits,” he said of the last four years.

By contrast, Romney promised that jobs, growth and the debt would be his priorities from the start. He pledged 12 million new jobs and a reduced deficit so that “investments in America will not vanish as have those in Greece.”

It has been refreshing this week to watch Republicans push the theme that they are prepared to lead and make tough choices. Politicians know that voters can get nervous when they start talking about reforming entitlement programs. But from Romney to Ryan to Christie, the convention’s major speakers didn’t shy away from the unpleasant truth that the government cannot sustain itself at current levels of spending.

But here’s another unpleasant truth: The tax-and-spending plans crafted in the House by Ryan, the vice presidential nominee, won’t balance the budget for about 20 years. That’s too long. And the plan would cut spending too deeply in some areas, such as programs benefiting the most vulnerable Americans.

As the campaign progresses, the GOP ticket needs to signal that Republicans will make tradeoffs, either in how they would reform the tax code or in the free pass they’ve given the Pentagon on budget cuts. This newspaper likes that Christie started down that road when he talked about principled compromise.

The other unpleasant reality is that Republicans should worry about alienating voters who don’t share the GOP’s increasingly hard-right social agenda. Suburban women, for example, continue to break sharply for Obama.

To her credit, Ann Romney unblinkingly took on this challenge. She appealed to female voters with an eloquent speech about her husband’s attributes, including his quiet service to others. The party needs to keep reaching out, including to Latinos who have been hit hard by the stagnant economy.

The GOP is clearly leaving Florida with a message to sell: We will lead. We will make tough choices. “Now is the moment when we can do something,” Romney said.

We like the take-charge spirit. The question now is, will Democrats meet this leadership challenge?